1.Field of the Invention
The present invention relates to a semiconductor package having a function of shielding electromagnetic interference (EMI), a manufacturing method thereof and a jig, and more particularly, to such a semiconductor package having an electromagnetic interference (EMI)-shielding function, a manufacturing method thereof and a jig for use in a plasma sputtering, in which a nickel alloy is coated on the surface of a semiconductor package by a sputtering method so as to shield electromagnetic interference (EMI) generated from the semiconductor package.
2.Background of the Related Art
Recently, since the development of semiconductors, the semiconductors have been employed in a variety of electronic products such as household electric appliances, industrial equipment, medical equipment, etc. The semiconductor-related technology follows a trend toward miniaturization, lightness and multifunction, and digitalization of the equipment is also rapidly promoted.
In general, semiconductor devices emit electromagnetic radiation in the range of from 50 MHz to 3 GHz depending on the speed of the microprocessor. Recently, along with the development of a high-speed microprocessor, and the rapid increase in both the demand for high-speed networking and switching capacity, the emission amount of the electromagnetic radiation increases. That is, along with digitalization of the electronic product, the amount of electromagnetic radiation emitted therefrom is gradually increasing. Such electromagnetic radiation acts as electromagnetic interference (EMI) or radio frequency interference (RFI) that hinders the operation of other electronic equipment. For instance, EMI or RFI causes a problem in that advanced equipment such as an automatic facility system, an aircraft or the like is erroneously operated, stops in its operation, etc. Such erroneous operation or operation stoppage may cause enormous property damage and even casualties.
Accordingly, there have been proposed methods for shielding EMI or RFI from the semiconductor devices. For instance, U.S. Pat. No. 7,109,410 discloses a shielded electronic package in which a metallized cover serving as an EMI shield is separately fabricated to shield electromagnetic interference (EMI) and is mounted in the semiconductor devices. However, the above-mentioned package has the disadvantage that the manufacturing cost is raised due to an increase in the number of parts in the case where the metallized cover is fabricated separately, and the assembling work of parts is cumbersome due to additional provision of a process for mounting the metallized cover. In addition, the conventional package has a limitation that it works against the semiconductor development trend toward miniaturization.
In the meantime, there has been proposed a method in which the surface of the semiconductor device is plated by using electroless plating or spraying. In case of the electroless plating method, it is required that the semiconductor device should be soaked in an etching solution or a chemical precipitation tank. Thus, in the case where it is impossible to immerse the electronic package in the etching solution or the chemical precipitation tank, the plating itself becomes impossible. In addition, in case of the spraying method, spray efficiency is deteriorated, and a sprayed thickness is thick and non-uniform, which is not suitable for forming a thin film.
Therefore, there is a need for the development of a method for forming an electromagnetic interference (EMI) shielding film, which can coat an EMI shielding thin film on the surface of the semiconductor device in a simple and convenient manner and can be applied to all kinds of semiconductor devices